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new testing procedure is introduced to evaluate the alactic running
performance in a 10s sprint task with near-maximal movement velocity.
The test is performed on a motor-equipped treadmill with inverted
polarity that increases mechanical resistance instead of driving the
treadmill belt. As a result, a horizontal force has to be exerted
against the treadmill surface in order to overcome the resistant force
of the engine and to move the surface in a backward direction. For
this task, subjects lean with their hands towards the front safety
barrier of the treadmill railing with a slightly inclined body posture.
The required skill resembles the pushing movement of bobsleigh pilots
at the start of a race. Subjects are asked to overcome this mechanical
resistance and to cover as much distance as possible within a time
period of 10 seconds. Fifteen male students (age: 27.7 ± 4.1 years,
body height: 1.82 ± 0.46 m, body mass: 78.3 ± 6.7 kg) participated
in a study. As the resistance force was set to 134 N, subjects ran
35.4 ± 2.6 m on the average corresponding to a mean running velocity
of 3.52 ± 0.25 m·s-1. The validity of the new test was
examined by statistical inference with various measures related to
alactic performance including a metabolic equivalent to estimate alactic
capacity (2892 ± 525 mL O2), an estimate for the oxygen
debt (2662 ± 315 ml), the step test by Margaria to estimate alactic
energy flow (1691 ± 171 W), and a test to measure the maximal strength
in the leg extensor muscles (2304 ± 351 N). The statistical evaluation
showed that the new test is in good agreement with the theoretical
assumptions for alactic performance. Significant correlation coefficients
were found between the test criteria and the measures for alactic
capacity (r = 0.79, p < 0.01) as well as alactic power (r = 0.77,
p < 0.01). The testing procedure is easy to administer and it is
best suited to evaluate the alactic capacity for bobsleigh pilots
as well as for any other running discipline.
KEY
WORDS: Alactic capacity, alactic power, metabolic cost, treadmill
test, bobsleigh.
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